Connected: An Internet Encyclopedia
RFC 1122 - 4.2.2.10 Simultaneous Open Attempts: RFC-793 Section 3.4, page

Top: Connected: An Internet Encyclopedia
Up: Requests For Comments
Up: RFC 1122
Up: 4. TRANSPORT PROTOCOLS
Up: 4.2 TRANSMISSION CONTROL PROTOCOL -- TCP
Up: 4.2.2 PROTOCOL WALK-THROUGH
Prev: 4.2.2.9 Initial Sequence Number Selection
Next: 4.2.2.11 Recovery from Old Duplicate SYN: RFC-793 Section 3.4, page 33

### 4.2.2.10 Simultaneous Open Attempts: RFC-793 Section 3.4, page 32

There is an error in Figure 8: the packet on line 7 should be identical to the packet on line 5.

A TCP MUST support simultaneous open attempts.

DISCUSSION:

  It sometimes surprises implementors that if two applications attempt to simultaneously connect to each other, only one connection is generated instead of two. This was an intentional design decision; don't try to "fix" it.

Next: 4.2.2.11 Recovery from Old Duplicate SYN: RFC-793 Section 3.4, page 33

Connected: An Internet Encyclopedia
RFC 1122 - 4.2.2.10 Simultaneous Open Attempts: RFC-793 Section 3.4, page